There are two great classes of Christian duties combined in the formation of Christian holiness—moral and positive; moral being the general effect of Christian principle, positive consisting in certain Christian acts. Now it is plainly in respect to these moral duties or duties of Christian principle that the natural heart finds the chief difficulty, and the outward acts of a ceremonial religion are incomparably easier than the holy dedication of a devoted heart. Hence it follows that the human heart is naturally prone to slide insensibly from the principle to the ritual, and to endeavour to compensate the defects of the one by a rigid attention to the requirements of the other. By such an accommodation no part of Divine truth is professedly set aside, but yet, by altering the proportions of the several parts, by throwing a strong light on one side of the picture, and a deep shade on the other, its whole character is completely changed, and religion is given to the natural man though his heart is left unsanctified by the Spirit. This tendency to substitute ritual for principle may be daily seen in every society. One thinks himself holy because he has kept his church; another, because he is a regular communicant; a third, because he attends daily service; a fourth, because he never neglects to say his prayers; while a fifth is quite sure that he is born again, because in his infancy he was baptized; although, possibly, neither one nor the other has learned anything of true holiness of heart. Out of this tendency has sprung up the whole system of Romish righteousness. The weed that grew out of the human heart it has adroitly cultivated, till it has become the strongest flower in its garden. What under the Gospel sprang up by nature against the Gospel it has embodied and arranged so as to become a substitute for the Gospel. Hence, under Popery, ritual has in many cases overpowered principle, and attention to ritual religion is made the substitute for spiritual holiness before God.